1. Field of the Invention
The present invention relates to a semiconductor device, in particular, to a semiconductor device including a porous layer covered by a poreseal layer.
2. Description of Related Art
Porous low-k material has a continuous open pore connectivity more than 0.7 nm. This causes the moisture and Copper (Cu) penetration into the porous low-k material. As results, the Cu diffusion causes the early TDDB failure and moisture outgas causes oxidization of a barrier metal to degrade the via open yields and Electro-Migration (EM) life time, as shown in FIG. 1. Therefore, a poreseal process is suggested by, for example, JP WO2004/107434, U.S. Pat. No. 7,541,679, U.S. Pat. No. 7,179,758, and U.S. Pat. No. 6,919,636. Otherwise, low-k repair method is suggested to improve just surface damage as the —(CH3)3 bond from chemistry adsorb —Si—O bonds, for example, by U.S. Pat. No. 7,541,200.